# Do tornados avoid big cities? **URL:** \ **Category:** Factual Questions\ **Created:** [June 18, 2004, 4:08pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058 "2004-06-18T16:08:12Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![StarvingButStrong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/starvingbutstrong/32/335_2.png) [@StarvingButStrong](https://boards.straightdope.com/u/StarvingButStrong)\ **Post date:** [June 18, 2004, 4:08pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/1 "2004-06-18T16:08:12Z")
I mean, we all know they go out of their way to trash trailer parks 😉 but is there something about big cities that repel them? I vaguely remember hearing that cities alter their local climate, though I don’t remember in what way. Does that perhaps tie into it? ---
**Author:** ![Lsura](https://avatars.discourse-cdn.com/v4/letter/l/7993a0/32.png) [@Lsura](https://boards.straightdope.com/u/Lsura)\ **Post date:** [June 18, 2004, 4:19pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/2 "2004-06-18T16:19:49Z")
[Nashville, 1998](http://www.srh.noaa.gov/ohx/surveys/nash_tor.htm) and from [this site](http://www.tornadoproject.com/myths/myths.htm) (partial quote - section begins about halfway down the page): > [@](#): > > In the past 40 years, the city of St. Louis and the surrounding suburbs of St. Louis County have been hit 22 times, although none of them were in the tiny skyscraper heart of the city. There are three possible reasons for that. First, the central city may produce a “heat island” in which turbulent rising air disrupts the formation of small tornadoes(keep in mind that most tornadoes are small). The second possibility is that the “roughness” created by the skyscrapers causes turbulence that disrupts the formation of small tornadoes. The third, is, of course, the idea that tornadoas are rare, and the central city is very small. So it is a matter of coincidence. > > Professor Fujita of the University of Chicago suggested that the “heat island” effect takes hold for small tornadoes when a city reaches a population of about 1,000,000. There seems to be a lack of small tornadoes in the central cities of Chicago, Tokyo, and London. These are the only three cities that have been carefully studied over a long time. > > None of this applies to intense tornadoes. They are just too rare to assume that they avoid central cities. There are thousands of small towns all across Tornado Alley that have never been hit by an intense tornado. If you have ever seen video of the Wichita/Andover, Kansas tornado, it should seem ridiculous to you to think that this monster, at the bottom of an 8-mile-high rotating column, would be bothered by the presence of a few 300-foot-tall buildings. Perhaps some time in the next century, a central city will be in the path of a violent tornado, and we will learn what will happen. The probability of a violent tornado in the downtown area of any large city is about once in a thousand years. ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [June 18, 2004, 4:26pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/3 "2004-06-18T16:26:57Z")
[Miami.](http://www.floridadisaster.org/bpr/Response/Plans/Nathaz/HazWX/Tornado/tornado.htm) ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [June 18, 2004, 4:27pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/4 "2004-06-18T16:27:11Z")
[Miami 1997](http://www.usatoday.com/weather/wtmiami.htm) - complete with cool picture. The main reason tornadoes avoid big cities is that taken as a % of total land in the Midwest (main area where tornadoes strike) it’s a very small number. ---
**Author:** ![Kent\_Clark](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kent_clark/32/105_2.png) [@Kent\_Clark](https://boards.straightdope.com/u/Kent_Clark)\ **Post date:** [June 18, 2004, 4:27pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/5 "2004-06-18T16:27:26Z")
I think Cecil once did a column about the “LaPorte weather anomoly” but my search didn’t turn one up. Here in tornado alley I can tell you from experience that _most_ tornados hit the suburbs. But the City of St. Louis is 61 square miles, while St. Louis County is 495 square miles, so the “suburbs” may just be a bigger target to hit. I do know that there have been at least three tornados on record that plowed right through the center of the city. Also, in many older areas the central city tended to be on a river while the suburbs were on higher ground, so it could also be that the funnel clouds may not always dip low enough to hit low ground. ---
**Author:** ![dwc1970](https://avatars.discourse-cdn.com/v4/letter/d/a183cd/32.png) [@dwc1970](https://boards.straightdope.com/u/dwc1970)\ **Post date:** [June 18, 2004, 5:15pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/6 "2004-06-18T17:15:27Z")
[Salt Lake City](http://www.disasterrelief.org/Disasters/990812SaltLake2/)’s downtown area was struck by a tornado in August of 1999. ---
**Author:** ![caveman](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/caveman/32/7242_2.png) [@caveman](https://boards.straightdope.com/u/caveman)\ **Post date:** [June 18, 2004, 5:35pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/7 "2004-06-18T17:35:35Z")
[Fort Worth](http://www.dallassky.com/fwtornado.htm) got the atmospheric smack-down as well… ---
**Author:** ![ioioio](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ioioio/32/316_2.png) [@ioioio](https://boards.straightdope.com/u/ioioio)\ **Post date:** [June 18, 2004, 8:57pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/8 "2004-06-18T20:57:43Z")
Downtown Memphis is supposedly safe from tornadoes because it is built on a bluff that shields the area from the tornadoes that sweep in from Arkansas. However, parts of town within a few miles of downtown have bit hit, as have the suburbs. ---
**Author:** ![Ringo](https://avatars.discourse-cdn.com/v4/letter/r/779978/32.png) [@Ringo](https://boards.straightdope.com/u/Ringo)\ **Post date:** [June 18, 2004, 9:36pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/9 "2004-06-18T21:36:07Z")
Houston has been hit several times, right in amongst the skyscrapers. ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [June 18, 2004, 10:11pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/10 "2004-06-18T22:11:28Z")
[Oaklahoma City](http://www.disasterrelief.org/Disasters/990505Oklahoma3/) 1999 [Dallas](http://www.stormtrack.org/library/historic/dal57.htm) 1957 ---
**Author:** ![Tapioca\_Dextrin](https://avatars.discourse-cdn.com/v4/letter/t/3d9bf3/32.png) [@Tapioca\_Dextrin](https://boards.straightdope.com/u/Tapioca_Dextrin)\ **Post date:** [June 18, 2004, 10:23pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/11 "2004-06-18T22:23:43Z")
[QUOTE=Lsura] and from [this site](http://www.tornadoproject.com/myths/myths.htm) > [@](#): > > There seems to be a lack of small tornadoes in the central cities of Chicago, Tokyo, and London. Chicago has been struck [86 times](http://www.crh.noaa.gov/lot/severe/SigChiTorn.html) in the last 150 years. ---
**Author:** ![Logitech](https://avatars.discourse-cdn.com/v4/letter/l/e19b73/32.png) [@Logitech](https://boards.straightdope.com/u/Logitech)\ **Post date:** [June 19, 2004, 12:04am UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/12 "2004-06-19T00:04:49Z")
You missed the [Edmonton](http://datalib.library.ualberta.ca/tornado/)[Tornado](http://www.ee.ualberta.ca/~rob/tornado87.htm) There is no specific reason for those sites, they were just the first ones I found under Edmonton +tornado, so there is no point to really visit them. ---
**Author:** ![Random](https://avatars.discourse-cdn.com/v4/letter/r/57b2e6/32.png) [@Random](https://boards.straightdope.com/u/Random)\ **Post date:** [June 19, 2004, 2:04am UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/13 "2004-06-19T02:04:16Z")
> [@Tapioca Dextrin](#): > > Chicago has been struck [86 times](http://www.crh.noaa.gov/lot/severe/SigChiTorn.html) in the last 150 years. No. From your link: “For the purpose of this study, the Chicago area is defined as McHenry, Lake, Kane, DuPage, Cook, Kendall, Will, and Lake (IN) counties.” That’s not Chicago. With one very minor exception, all of Chicago is located in Cook County, and covers only about 25% of that. Further, buildings in Chicago (or any of the mentioned counties) over 10 stories are concentrated in area of about 5 square miles. (Chicago covers 228 square miles.) I am aware of only 2 tornadoes that have ever caused significant damage in Chicago, and both were on the outskirts. The eight-county area mentioned in the link was mostly farmland until relatively recently (a lot still is), and of the parts that are now urban, single-family homes and one or two story commercial buildings predominate. ---
**Author:** ![HeyHomie](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heyhomie/32/207_2.png) [@HeyHomie](https://boards.straightdope.com/u/HeyHomie)\ **Post date:** [June 19, 2004, 11:26am UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/14 "2004-06-19T11:26:48Z")
Mentioned so far: Miami Oklahoma City Dallas/Ft. Worth Nashville St. Louis Chicago 'burbs Edmonton There’s also: Topeka, KS (pop: 120,000ish) Andover, KS (suburb of Wichita) Kissimmee, FL (suburb of Orlando) Ft. Smith, AR (pop: 105,000ish) ---
**Author:** ![StarvingButStrong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/starvingbutstrong/32/335_2.png) [@StarvingButStrong](https://boards.straightdope.com/u/StarvingButStrong)\ **Post date:** [June 19, 2004, 1:29pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/15 "2004-06-19T13:29:35Z")
Okay, my impression that cities were immune is clearly a result of my sampling error. Besides this: > [@Tapioca Dextrin](#): > > The main reason tornadoes avoid big cities is that taken as a % of total land in the Midwest (main area where tornadoes strike) it’s a very small number. which no doubt accounts for a lot of it, there’s a bias on the part of news reports to show the worst, most damaged results of any disaster. From the linked reports I read (not all of them, I admit) but in general when a tornado actually went through the center of a big urban area, the reported damage consisted of broken windows, limbs broken off trees, and some roof damage. Clearly high-rise building are ‘sturdier’ in whatever way it takes to resist tornado damage. In contrast, one-story suburban houses often lose their entire roofs, and often whole sections of walls as well. And ‘manufactured housing’, as the trailer-home industry wants them called, seem to basically explode when a tornado passes over. Given that the urban damage isn’t all that photogenic, I bet even when a tornado does hit a city, what is shown on screen is shots of the more damaged suburbs while the fact that the city was hit is just mentioned verbally. ---
**Author:** ![AncientHumanoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ancienthumanoid/32/278_2.png) [@AncientHumanoid](https://boards.straightdope.com/u/AncientHumanoid)\ **Post date:** [June 19, 2004, 2:50pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/16 "2004-06-19T14:50:20Z")
Just to add: The May 3rd, 1999 F5 that hit the OKC metro area had the highest windspeed recorded on Earth. [318mph (measured by doppler radar)](http://www.hprcc.unl.edu/nebraska/may3outbreak.html) [May 8th, 2003,](http://windstormcomputing.com/) an F4 took almost the same path. ---
**Author:** ![AncientHumanoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ancienthumanoid/32/278_2.png) [@AncientHumanoid](https://boards.straightdope.com/u/AncientHumanoid)\ **Post date:** [June 19, 2004, 3:01pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/17 "2004-06-19T15:01:09Z")
[Arial photo of part of the May 3rd F5 damage.](http://www.rogerbondy.com/56781-tornado-path-moore-oklahoma.htm) Note the complete destruction of homes in the path. I was involved in the clean up / rebuild of one neighborhood (West Moore, OK). Let me tell you, the destruction was very severe. In some places (Bridgecreek, OK), the concrete roads were blown away. Yeah, the wind took the freakin’ road! ---
**Author:** ![percypercy](https://avatars.discourse-cdn.com/v4/letter/p/8baadc/32.png) [@percypercy](https://boards.straightdope.com/u/percypercy)\ **Post date:** [June 19, 2004, 5:15pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/18 "2004-06-19T17:15:13Z")
> [@lainaf](#): > > Downtown Memphis is supposedly safe from tornadoes because it is built on a bluff that shields the area from the tornadoes that sweep in from Arkansas. However, parts of town within a few miles of downtown have bit hit, as have the suburbs. I think that’s right, for the most part, but last summer we had straight line winds through the whole city including most definitely downtown that knocked out power in some parts for weeks. We had gusts of 75-95 miles an hour. Like a category one hurricane. There’s a few pictures here. [http://www.david-albert.biz/Storm2003/NewPaper.html](http://www.david-albert.biz/Storm2003/NewPaper.html) ---
**Author:** ![BobT](https://avatars.discourse-cdn.com/v4/letter/b/8e8cbc/32.png) [@BobT](https://boards.straightdope.com/u/BobT)\ **Post date:** [June 19, 2004, 5:36pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/19 "2004-06-19T17:36:05Z")
Although I can’t find the date, there was a small tornado that touched down in Downtown L.A. about 15 years ago. It did most of its damage around the Convention Center. ---
**Author:** ![fruitbat](https://avatars.discourse-cdn.com/v4/letter/f/58f4c7/32.png) [@fruitbat](https://boards.straightdope.com/u/fruitbat)\ **Post date:** [June 19, 2004, 6:20pm UTC](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058/20 "2004-06-19T18:20:25Z")
In 1953 a tornado with then record winds of 250 mph roared through Worcester, MA. The pictures of JFK touring the damage are really quite amazing. [Next page](https://boards.straightdope.com/t/do-tornados-avoid-big-cities/251058.md?page=2)